Metal Forming: Extrustion and Forging
40 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

In which type of extrusion process, the ram moves in the same direction of the extruded product?

  • Hydrostatic extrusion
  • Radial extrusion
  • Direct extrusion (correct)
  • Indirect extrusion
  • What is the main advantage of indirect extrusion over direct extrusion?

  • Higher frictional forces
  • Lower frictional forces (correct)
  • Increased production rate
  • Reduced material cost
  • Radial extrusion is commonly used for production of which type of components?

  • Circular components
  • Flange type components (correct)
  • Tubular components
  • Square components
  • What is the main characteristic of impact extrusion process?

    <p>Quick movement of the punch</p> Signup and view all the answers

    What is the advantage of hydrostatic extrusion over conventional extrusion?

    <p>Improved ductility of the material</p> Signup and view all the answers

    What type of forging process is used to form heads of nails, bolts, and other hardware products?

    <p>Upset forging</p> Signup and view all the answers

    What is the main advantage of metal forming over other manufacturing processes?

    <p>Minimal material wastage and better mechanical properties</p> Signup and view all the answers

    What is the force required to deform a metal block in metal forming?

    <p>Higher than the yield strength of the material</p> Signup and view all the answers

    What are the two major sections of metal forming processes?

    <p>Bulk metal working and sheet metal working</p> Signup and view all the answers

    What are the advantages of cold forging and extrusion processes?

    <p>Geometrical accuracy, surface finish, and mechanical properties</p> Signup and view all the answers

    How many types of extrusion processes are classified based on the relative movement of the punch and extruded product?

    <p>Four</p> Signup and view all the answers

    What is the temperature range at which extrusion and forging processes can be carried out?

    <p>Hot, cold, and warm temperatures</p> Signup and view all the answers

    What is the main benefit of closed die forging?

    <p>It provides a multidirectional unbroken grain flow inside the product</p> Signup and view all the answers

    What is flashless forging?

    <p>A type of forging where the volume of the workpiece is equal to the volume of the die cavity</p> Signup and view all the answers

    What is the main advantage of combined extrusion-forging process?

    <p>It reduces the capital investment and produces net or near-net shape products</p> Signup and view all the answers

    What is the significance of combined extrusion-forging process in modern industry?

    <p>It is used to produce complex shapes with better mechanical properties</p> Signup and view all the answers

    What is the role of dies in metal extrusion and forging?

    <p>They are the replica of the profile which is to be extruded or forged</p> Signup and view all the answers

    What is the advantage of using aluminium and aluminium based alloys in combined extrusion-forging process?

    <p>They minimize cracks in the material in the initial breakdown of the ingot</p> Signup and view all the answers

    What is the primary requirement for dies used in the manufacturing process?

    <p>Higher mechanical characteristics and dimensional accuracy</p> Signup and view all the answers

    Which type of die is most preferred in the industry due to its simple design and low cost?

    <p>Flat faced dies</p> Signup and view all the answers

    What is the primary advantage of metal spinning over stamping and deep drawing processes?

    <p>Lower capital investment</p> Signup and view all the answers

    What is the main function of the roller in the metal spinning process?

    <p>To press the metal against the tool</p> Signup and view all the answers

    What is the primary advantage of curved dies over flat faced dies?

    <p>Minimization of friction loss and redundant work</p> Signup and view all the answers

    What is the main advantage of metal spinning in terms of production quantities?

    <p>Economical for one-off parts, prototypes, and small, medium, and high volumes</p> Signup and view all the answers

    What is the primary advantage of metal spinning?

    <p>It requires a short lead time for parts</p> Signup and view all the answers

    What is the main difference between hot spinning and cold spinning?

    <p>The temperature of the metal blank</p> Signup and view all the answers

    What is the primary application of cold spinning?

    <p>Production of light reflectors and cooking utensils</p> Signup and view all the answers

    What is the process of drawing used for?

    <p>Forming a flat precut metal blank into a hollow vessel</p> Signup and view all the answers

    What is the primary difference between wire drawing and extrusion?

    <p>The direction of the force applied</p> Signup and view all the answers

    What is the primary purpose of tube drawing?

    <p>To decrease the diameter of the tube</p> Signup and view all the answers

    Which of the following is NOT a type of metal forming process?

    <p>Machining</p> Signup and view all the answers

    What is the main advantage of metal forming over other manufacturing processes?

    <p>High precision in production of complex shapes with minimal material wastage</p> Signup and view all the answers

    Which of the following is a type of bulk metal working process?

    <p>Forging</p> Signup and view all the answers

    What is the result of applying a force higher than the yield strength of the material in metal forming?

    <p>Deformation of the material</p> Signup and view all the answers

    Which of the following is a characteristic of cold forging and extrusion processes?

    <p>High dimensional accuracy</p> Signup and view all the answers

    What is the main difference between hot and cold forging processes?

    <p>Temperature range</p> Signup and view all the answers

    Which of the following is a type of extrusion process?

    <p>Forward extrusion</p> Signup and view all the answers

    What is the main advantage of using metal forming in the manufacturing process?

    <p>Economic in comparison with other conventional manufacturing processes</p> Signup and view all the answers

    Which of the following is a characteristic of radial extrusion?

    <p>Material flow perpendicularly to the direction of the punch movement</p> Signup and view all the answers

    Which of the following is an example of a product manufactured using impact extrusion?

    <p>Toothpaste tubes</p> Signup and view all the answers

    Study Notes

    Conventional Manufacturing Processes

    • Metal forming has advantages over other manufacturing processes due to high precision, minimal material wastage, and better mechanical properties.
    • Metal forming is a process of plastically deforming a metal block to a desired geometry by applying a force higher than the yield strength of the material.

    Bulk Metal Working Processes

    • Classified into four types: rolling, forging, extrusion, and drawing.
    • Forging and extrusion are frequently used forming processes since the 18th century.

    Extrusion and Forging Processes

    • Can be carried out under three working temperatures: hot, cold, and warm linked to recrystalization temperature.
    • Cold forging and extrusion processes have more advantages compared to hot and warm processes with respect to geometrical accuracy, surface finish, and mechanical properties of the final component.

    Extrusion Processes

    • Classified into four types depending on the relative movement of the punch and extruded product:
      • Forward (Direct) extrusion: most common method used in industries to manufacture long products of uniform cross-section.
      • Backward (Indirect) extrusion: billet does not move relative to the container, eliminating frictional force between billet and container interface.
      • Radial (Lateral) extrusion: material flow perpendicularly to the direction of the punch movement.
      • Impact extrusion: similar to backward/indirect extrusion process, with a punch running down quickly on the blank to obtain a tubular section.

    Forging Processes

    • Classified into:
      • Upset forging: force applied parallel to the length direction to increase the cross-section at the expense of length.
      • Drawing out: force applied perpendicular to the length axis to decrease the cross-section area.
      • Open die forging: work is compressed between two flat dies, allowing metal to flow freely laterally.
      • Closed die or Impression die forging: work piece is compressed between two die halves to obtain a multidirectional unbroken grain flow.
      • Flashless forging: volume of the workpiece is equal to the volume of the die cavity, with no requirement of flash arrangement.

    Combined Extrusion Forging Processes

    • Combined forward and backward extrusion (CE): simultaneous backward and forward extrusion.
    • Combined extrusion-forging (CEF): both extrusion and forging take place simultaneously to obtain a complex shape.

    Dies

    • Types of dies:
      • Flat faced dies: most preferred in the industry due to its simple design and low cost.
      • Taper or conical dies: have an entrance angle for metal flow.
      • Curved dies: minimize friction loss and redundant work.

    Metal Spinning

    • A process of forming rotationally symmetrical hollow parts from circular blanks.
    • Used to produce cone-shaped, elliptical, or other concave or convex parts.
    • Metal spinning yields pots, pans, vases, lamp shades, musical-instrument parts, and trophies.

    Drawing

    • A process of cold forming a flat precut metal blank into a hollow vessel.
    • Various forms produced include cylindrical, box-shaped, and irregular shapes.
    • Used to produce cups, cans, pans, cylinders, domes, hemispheres, tubes, and hoppers.

    Wire Drawing

    • A metalworking process used to reduce the cross-section of a wire by pulling the wire through a single, or series of, drawing die(s).
    • Used to produce electrical wiring, cables, tension-loaded structural components, springs, and paper clips.

    Tube Drawing

    • A process similar to bar drawing, used to decrease the diameter, improve surface finish, and improve dimensional accuracy of tubes.

    • A mandrel may or may not be used depending on the specific process used.### Types of Extrusion

    • Direct extrusion: billet moves relative to the container

    • Indirect (Backward or Reverted) extrusion: billet does not move relative to the container, die fixed on a hollow ram pushes against the billet, eliminating frictional force between billet and container interface

    • Radial (Lateral) extrusion: material flow perpendicularly to the direction of the punch movement, requiring additional power to overcome friction at the die-billet interface, commonly used for production of flange type components

    • Impact extrusion: similar to indirect extrusion, punch runs down quickly on the blank, resulting in a tubular section, used to produce toothpaste tubes

    • Hydrostatic extrusion: billet is extruded through the die by the action of a hydrostatic liquid pressure medium, rather than direct application of load with a ram, allows for extrusion of brittle materials, can be done hot, warm, or cold

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    This quiz covers the basics of metal forming, a manufacturing process used in automobile and aircraft industries, focusing on extrusion and forging techniques. It discusses the advantages of metal forming over other processes, including high precision and minimal material wastage.

    More Like This

    Use Quizgecko on...
    Browser
    Browser